Washington military experts are planning for the occupation of North Korea if knife-edge tension over Kim Jong-un's nukes spills over into all-out war, it has been reported.
Military advisers claim the impoverished Asian nation would soon collapse - with a huge loss of life in both South and North Korea - if America and its allies invaded, reports The Sun.
But US President Donald Trump's generals and advisers are said to be concerned that a fanatical insurgency would bog down US forces for years.
Laura Rozen, a journalist for Al-Monitor, said a source told her that think tank advisers linked to Mr Trump are "quietly preparing studies on the aftermath of war with North Korea".
She added that these experts are using lessons from armed rebellion during the American occupation of Iraq.
She wrote: "There's a lot of interest in studies on how to defeat insurgencies led by former regime types armed with chemical and biological agents."
And Mark Fitzpatrick, the executive director of the International Institute for Strategic Studies office in Washington, toldThe New Yorker that Kim's fanatical soldiers might use guerilla tactics against US forces in the North.
He said: "A war would not end quickly after the defeat of North Korean forces. North Korea would not be immediately pacified."
He added: "North Koreans are brainwashed into believing that the Kim dynasty is deity-like and Americans are the source of all evil."
Meanwhile, the standoff over North Korea could lead to "nuclear war", a Japanese pro-wrestler turned politician warned, urging nations to dial down the tension after the isolated country fired a missile over northern Japan last month.
Tokyo could play a role in mediating with its neighbour, said 74-year-old Antonio Inoki, who is known for fighting boxer Muhammad Ali four decades ago.
"We are seeing a situation where each raises his fist and the situation is escalating," Mr Inoki, who recently returned from his 32nd visit to Pyongyang, told a news conference, wearing his signature red scarf.
"It's important to see who can be the first to lower his fist and reduce the tension," said Inoki, who, like US basketball star Dennis Rodman, has made numerous visits to North Korea.
Pyongyang must commit to denuclearisation as a prerequisite for talks, Japanese Prime Minister Shinzo Abe said in an interview with the Nikkei business daily published on Wednesday.
On Monday, the UN Security Council voted to tighten sanctions on the North over its sixth nuclear test.